In interval flush mode, a flush takes place at regular intervals if the drinking water installation is not in use or is only used to a limited extent. There is no fixed flush point in this operating mode. This makes it possible to comply with the requirements regarding regular water replacement in accordance with DIN EN 806-5 and VDI/DVGW 6023-1.

1. Image: In interval flush mode, a flush takes place at regular intervals.
2. Image: Example of piping of an interval-controlled concealed cistern with hygiene flush unit

The time-based flush starts at fixed times. It starts at a specified time of day (e.g. 6:00 p.m.), combined with one or more days of the week (e.g. Tuesday, Thursday and Sunday). When actuated, the flush lasts for a specified, adjustable flush time.

1. Image: Example of piping of an interval-controlled hygiene flush unit with two classrooms, WC and technical room
2. Image: Example of piping of a time-controlled hygiene flush unit

Flushing the pipes in rooms where water temperatures reach the critical range due to the use of the room. In this operating mode, the flush starts when a particular temperature is reached (e.g. standard specification for PWC max. 25°C). The flush ends either when a stop temperature is reached or after a maximum predetermined flush time.

If the specified temperature is not exceeded within a predetermined time frame, the control actuates a routine flush. The routine flush is interval-based. The enable time can be used to set a time frame during which the hygiene flush unit should not actuate a flushing process (e.g. from 10:00 p.m. to 8:00 a.m. in hotels).

Figure 1: Example of piping of a temperature-controlled hygiene flush unit using the example of a service connection room and a plant room with a room temperature >25°C.
Figure 2: Example of piping of a temperature-controlled concealed cistern with hygiene flush unit and using a temperature sensor.